• Title/Summary/Keyword: hop

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A review study on the Yug Bu Ha Hap Hyul (육부하합혈(六腑下合穴)의 도입(導入) 배경(背景)에 관(關)한 연구(硏究))

  • Lee, Bong-Hyo;Lim, Sung-Chul;Lee, Kyung-Min;Kim, Jae-Su;Jung, Tae-Young
    • Korean Journal of Acupuncture
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    • v.26 no.3
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    • pp.77-85
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    • 2009
  • Objectives : The lower sea points of the six bowels is one of the most useful acupuncture prescription in the treatment for diseases related with six organs. There have been many studies on the effects of each acupoint, but it is difficult to find a systemic review about the whole of it. The purpose of this study is to review the lower sea points of the six bowels and investigate the background of the induction of that. Materials and Methods : 1. The authors performed systemic review about the lower sea points of the six bowels using related-literatures such as Neijing and Nanjing. 2. We investigated the background of the induction and the necessity through the meaning of the character Hop (合). We thought the clinical usefulness of that. Results and Conclusions : The lower sea points of the six bowels had been made for the supplement of the sea point of the five transport points and it might be possible to substitute the sea point of the five transport points with the lower sea points of the six bowels owing to the clinical usefulness of the lower sea points of the six bowels.

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The Effect of Green Tea Extracts on the Fermentation Properties of Polyphenol-Enriched Beers (녹차 추출물을 첨가한 polyphenol 강화 맥주의 발효 특성에 대한 연구)

  • Yom, Heng-Cherl
    • Journal of the Korean Home Economics Association
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    • v.46 no.3
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    • pp.49-55
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    • 2008
  • The purpose of this study was to investigate the effects of green tea extracts (GTE) on the fermentation properties of polyphenol-enriched beers. As such, the formation patterns of tannoid in beer with GTE were investigated at 3 different infusion times, while the ale and the lager beers fortified with GTE were analyze to ascertain effects on gravity, pH, yeast viability, total polyphenol, and tannoid during fermentation period. The results were as follows: 1) The formation of tannoid in beer with GTE in the tannometer; In reaction of GTE with polyvinylpyrrolidon (PVP), control lager beer peaked in the formation of tannoid at $70\;{\sim}\;80\;mg$ of PVP, the 1st extract exceeded the detection limit, the 2nd extract at $170\;{\sim}\;180\;mg$, while the third extract at $150\;{\sim}\;160\;mg$ of PVP. The GTE were slow in reacting with PVP, and their formation patterns were different from those of polyphenols from barley and hop. 2) Ale fermentation; The final alcohol content was 9.25% (ABV). The addition of GTE increased the yeast viability after 2 days and finally reached 52.3% from 30.9%. Total polyphenol in GTE beer increased by 1.5 times (p < .05). However, its tannoid contents increased by 6.4 times. 3) Lager fermentation; The final alcohol content was 5.93% (ABV). The effect of GTE on lager beer was minimal for all variables. However, total polyphenol of GTE beer increased by 1.4 times (p < .05). Its tannoid increased by 3.3 times (p < .05).

WDMA protocol with collision avidance for high speed optical networks (고속 광통신망에서 충돌 회피를 위한 파장 분할 다중 액세스 프로토콜)

  • 이호숙;최형원;박성우;김영천
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.21 no.3
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    • pp.664-674
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    • 1996
  • In high speed multi-wavelength networks, retransmission overhead due to desination conflict or control packet collision is one factor of performance degration because signal prpagation delay is much larger than the transmission time of data packet. In this paper, an efficient WDMA protocol with a collision avoidance mechanism is proposed for high speed WDM single-hop network with a passive star topology. In proposed protocol, each node has cource queues and routing table to store souting informatio. This architecture makes is possible to avoid any kind of collision when a node reserves the channel to transmit a data packet. High system thoughput and channel utilization can be achieved by proposed protocol since there are no discarded packets caused by any collision at transmission time. The performance of proposed protocol is evaluated in term of throughput and delay with variations in offered load. Simulation results show that the proposed protocol has superior performance to convertional protocols under nonuniform traffic as well as uniform traffic.

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Adaptive Dual-Hop Transmission Based On Hierarchical Modulation in UWB System (초광대역 시스템의 계층변조 기반 적응적 듀얼 홉 전송 기법)

  • Kim, Dae-Hwan;Song, Hyoung-Kyu;Cho, We-Duke
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.36 no.7C
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    • pp.443-450
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    • 2011
  • Recently, various transmission techniques for communication and broadcasting systems have been developed to meet the dramatically increasing requirement of consumers. Because UWB (Ultra-Wideband) is a wireless communication technique that supports high data rate with low power, it can satisfy the requirement and can be applied to various wireless communication services. The multi-band orthogonal frequency division multiplexing (MB-OFDM) system, one of UWB system, is the wireless communication system that satisfies the transmission characteristic for UWB and so it can be used for various wireless communication services. In this paper, we propose a scheme that uses hierarchical modulation which is applied in digital video broadcasting system at the source and adaptive modulation based on the channel quality at the relays. The simulation results have shown that the proposed scheme has both the advantages of the increased throughput by 33% and similar BER performance to conventional scheme.

Performance Analysis of Position Based Routing Protocol for UAV Networks (UAV 네트워크 환경에 적합한 위치기반 라우팅 프로토콜의 성능 분석)

  • Park, Young-Soo;Jung, Jae-Il
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.37 no.2C
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    • pp.188-195
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    • 2012
  • Many systems are developing for the realization of NCW(Network Centric Warfare). UAV(Unmanned Aerial Vehicle) Network is attracting attention in a lot of military applications. In general, UAVs have the potential to create an ad-hoc network and greatly reduce the hops from source to destination. However, UAV networks exhibit unique properties such as high mobility, high data rate, and real time service. The routing protocols are required to design the multi-hop routing protocols that can dynamically adapt to the requirements of UAV network. In this paper we analyse Geographic Routing Protocol is based on geographical distance between source and destination for efficient and reliable transmission. Geographic Routing Protocol is evaluated in video service scenarios with TDMA model in our simulation. The simulation results show that the performance of Geographic Routing Protocol is better than the MANET Routing Protocol in terms of packet received ratio, end to end delay, and routing traffic sent.

Design and Implementation of Multi-rate Broadcast based Link Quality Measurement for WLAN Mesh Network (다중 전송률을 반영한 무선랜 매쉬 링크 품질 측정방법의 설계 및 구현)

  • Lee, Duck-Hwan;Yang, Seung-Chur;Kim, Jong-Deok
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.36 no.9A
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    • pp.801-808
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    • 2011
  • We propose MBAP(Multi-rate Broadcast Active Probing) technique to get the right measurements for link quality in Wireless Mesh Network (WMN). Most routing protocols for WMN make use of link quality-aware routing metrics, such as ETX(Expected Transmission Count) and ETT(Expected Transmission Time), while the hop count is usually used in MANET (Mobile Ad-hoc NETwork). A broadcast based active proving technique is adopted in the previous studies to get the ETX or ETT of a link. However this technique does not reflect the multi-rate feature of WLAN because it uses a single fixed transmission rate for broadcast which usually differs from the actual rate used in data transmissions. MBAP overcomes this shortage by exploiting various rate broadcast frames for probing. We implement MBAP on linux system by modifying WLAN driver and related kernel sub-systems. Experimental results show that MBAP can capture link quality more accurately than the existing techniques.

Effective Emergency-Warning Message Transmission in the Vehicle-to-Vehicle Communication Environment (차량 간 통신 환경에서 효과적인 위험 경고 메시지 전송 방안)

  • Byun, Jae-Uk;Kwon, Sung-Oh
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.37 no.1B
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    • pp.1-8
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    • 2012
  • In this paper, we propose an algorithm to improve collision avoidance in Vehicle-to-Vehicle (V2V) networks based on IEEE 802.11p. Since IEEE 802.11p adopts CSMA/CA as a multiple access scheme and an emergency warning message (EWM) is delivered to behind vehicles in a multi-hop manner, due to transmission collision, the more vehicles in the vehicle chain results in a longer delay. The longer delay increases the possibility of a rear-end collision. In order to ensure message reception with low latency, we consider implicit acknowledgement of a broadcasted EWM message and propose an algorithm to reduce redundant message transactions, called Two-Way Implicit Acknowledgement (TWIA). By simulations, we show that our proposed algorithm can reduce the latency until the last car receives the message by 9% and the success rate every car receives the message within 0.7sec by 12% at 100 fixed-number-of-car environment.

Publish/Subscrib Service based Selective Sensor Data Monitoring System using Mesh Network (메쉬 네트워크에서 가입/게시(subscribe/publish) 서비스기반 선택적 센서정보 모니터링 시스템)

  • Kim, Yong-Hyuck;Kim, Young-Han
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.35 no.3B
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    • pp.493-502
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    • 2010
  • In this paper we propose a scalable sensor network system that makes mesh network among the sink nodes to solve the scalability problem of existing sensor network which is caused by multi-hop networking between the sensor nodes. In the proposed system, the sink nodes have the wireless networking ability to communicate with another sink nodes in mesh fashion, and with the monitoring nodes which is located in the local area or internet area. Especially, the system includes L4(Application Layer) routing mechanism that provides subscribe/publish service to serve selective transmission of sensor data to the specific monitoring nodes. The collected sensor data is transmitted to the monitoring nodes when the sensor data is matched with the monitoring node's interesting value.

An Efficient Service Discovery for Mobile Ad Hoc Networks (모바일 애드-혹 네트워크를 위한 효율적인 서비스 디스커버리)

  • Kang, Eun-Young
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.9B
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    • pp.947-954
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    • 2009
  • In mobile ad hoc networks, service discovery to search for an available service is an important issue. In this paper, we propose an efficient service discovery protocol that is combined a dht-based service discovery scheme and a P2P caching-based information spreading scheme. Proposed scheme store key information in hashed zone and search services using it's information. To search quickly a service, it use its physical neighbors information which collected by 1-hop hello message between a node and its physical neighbors. We do not use a central look up server and do not rely on flooding. Hence, it uniquely balanced all node's load in mobile ad hoc networks and reduced the number of messages exchanged, network load and response time. The simulation results show that our protocol outperforms DHT-based and flooding protocols.

Interference-Free Multipath Routing Protocol for M2M Wireless Network to Enhance Packet Delay Performance (M2M 무선 네트워크에서 패킷 지연 성능 향상을 위한 간섭 회피 다중 경로 라우팅 기법)

  • Heo, Hyeong-Min;Hwang, Jun-Ho;Yoo, Myung-Sik
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.35 no.12B
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    • pp.1259-1266
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    • 2010
  • M2M communication is considered as a key enabling technology to monitor the status of objects, vehicles, humans through auto-configuring wireless networks. In M2M network, there are active research activities to enhance the reliability on data while being collected from wireless sensor network. The reliability issue becomes more important as wireless sensor networks carry multimedia data, which is delay sensitive. The interference caused by the adjacent neighbor sensor nodes is a major factor in network performance degradation, which becomes more severe in multi-hop routing environment. In this paper, we propose inerfernce-free multipath routing protocol for M2M wireless network for enhancement of packet delay performance. The simulation results show that the proposed routing algorithm outperforms the existing routing protocols in terms of packet delay and throughput.